[TowerTalk] Verticals of Telescoping Aluminum

Dinsterdog@aol.com Dinsterdog@aol.com
Sat, 9 Sep 2000 18:22:13 EDT


In constructing my 80 meter 4-sqr array, I used aluminum verticals.  Each 
vertical is 52 feet tall, made up of 6 foot sections of aluminum.  I have 
each piece of aluminum sunk 3 inches into each lower section.  To secure the 
pieces together, I ran 2 bolts, 180 degrees to one another, at the 1 inch and 
2 inch marks.  I used conductive grease at the joints and tightly secured a 
hose clamp at the top of each intersection.  The aluminum diameter starts at 
2.125x.058 and progresses up at 1/8 inch diameter increments.

I can raise the antennas by myself, using the assistance of a weighted down 
fold out ladder with a exstenion ladder tied to it, pulled out about 3 feet 
from where the antenna is going to be centered and raised about 20 feet in 
the air. 

I use a piece of PVC pipe sitting 6 inches above the ground to set the 
antenna upon once raised.   

When raising the antenna via the extension ladder, the tip of the antenna 
almost bows over and touches the ground, until I have a chance to push the 
antenna up the ladder rail until it goes vertical.  With the top of the 
ladder rung at around 20 feet, the strength of the verticals is exceptional.  
For at one point,  while pushing the antennas up in the air,  the antenna is 
centered on top of this rung with 1/2 the antenna on each side of it- 
weighted down by guy ropes and top hat wires....it bends but survives fb and 
then eventually goes vertical once I have pushed the antenna far enough up 
the ladder-  -

I use guy ropes to secure the antenna only AFTER the antenna is raised, with 
it resting against the ladder and secured by bungie cord straps.  If you use 
this method, you can't weigh down your ladders enough-  I use three 80lb 
concrete bags laying accross the fold out ladder, and it still seems not 
enough at times, especially in the wind-  but it works-

My suggestion is that if you need a set of guys to keep your current aluminum 
antenna from folding over on itself as is, - you might want to go to heavier 
aluminum, or shorter sections to provide more strength. 

GL 73  Paul  N0AH 

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